Gelation Properties and Spectroscopic Analysis of 2-Oxochromen-6-yl 4-Alkoxybenzoates with Organic Solvents

Several 2-oxochromen-6-yl 4-alkoxybenzoates were able to gelate n-octane and propylene carbonate in added amounts of 5 wt % or less. Gelation abilities of the compounds were affected by exhibited liquid crystal phase in bulk state. 5 wt %n-octane gels formed by the compounds exhibited smectic A phases and thixotropy due to similar viscosities before and after shear. When the compounds gelated n-octane, they self-assembled by dipole-dipole interaction between coumarin skeletons and hydrophobic interaction between alkyl chains, which are supported by IR, UV-Vis spectra and DFT calculation.